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From: white@leadsv.UUCP (Ben White)
Newsgroups: comp.unix.questions
Subject: Re: loginid vs. uid.
Summary: Is that so?
Message-ID: <12274@leadsv.UUCP>
Date: 19 Jul 90 16:39:31 GMT
References: <11399@hydra.gatech.EDU> <232@twg.wimsey.bc.ca> <9900@crdgw1.crd.ge.com>
Organization: LOCKHEED, Sunnyvale, CA
Lines: 16

In article <9900@crdgw1.crd.ge.com>, volpe@underdog.crd.ge.com (Christopher R Volpe) writes:
> What exactly does su have to do (when given the "-" option) to *completely*
> change your identity so that applications like mail think you are the
> person you su'd to rather than the person you su'd from? ...
>
> ... mail still thought I was the person I logged in under.
> Does mail use the utmp file as well? I tried changing enironment
> variables such as HOME and LOGNAME, but they had no effect. 

What version of UNIX are you running, and on what machine?
I have run a similar setruid/seteuid program on SunOS (4.0.3),
and mail seems operate properly with the "new" userid.  Likewise for
just about everything else I've tried, except of course, "who", which
uses the utmp file, as you pointed out.

Ben White